Curcumin is the active ingredient of turmeric. It is widely used as a kitchen spice and food colorant throughout India, Asia and the Western world. Curcumin is a major constituent of curry powder, to which it imparts its characteristic yellow colour. For over 4000 years, curcumin has been used in traditional Asian and African medicine to treat a wide variety of ailments. There is a strong current public interest in naturally occurring plant-based remedies and dietary factors related to health and disease. Curcumin is non-toxic to human subjects at high doses. It is a complex molecule with multiple biological targets and different cellular effects. Recently, its molecular mechanisms of action have been extensively investigated. It has anti-inflammatory, antioxidant and anti-cancer properties. Under some circumstances its effects can be contradictory, with uncertain implications for human treatment. While more studies are warranted to further understand these contradictions, curcumin holds promise as a disease-modifying and chemopreventive agent. We review the evidence for the therapeutic potential of curcumin from in vitro studies, animal models and human clinical trials.

Archaeological evidence from dry cave deposits in the northern Chihuahuan Desert reveal intensive utilisation of desert plants that store prebiotic inulin-type fructans as the primary carbohydrate. In this semi-arid region limited rainfall and poor soil conditions prevented the adoption of agriculture and thus provides a unique glimpse into a pure hunter–forager economy spanning over 10 000 years. Ancient cooking features, stable carbon isotope analysis of human skeletons, and well-preserved coprolites and macrobotanical remains reveal a plant-based diet that included a dietary intake of about 135 g prebiotic inulin-type fructans per d by the average adult male hunter–forager. These data reveal that man is well adapted to daily intakes of prebiotics well above those currently consumed in the modern diet.

Psychological stress is a common feature of modern day societies, and contributes to the global burden of disease. It was proposed by Henry over 20 years ago that the salt intake of a society reflects the level of stress, and that stress, through its effect on increasing salt intake, is an important factor in the development of hypertension. This review evaluates the evidence from animal and human studies to determine if stress does induce a salt appetite and increase salt consumption in human subjects. Findings from animal studies suggest that stress may drive salt intake, with evidence for a potential mechanism via the sympatho-adrenal medullary system and/or the hypothalamo–pituitary–adrenal axis. In contrast, in the few laboratory studies conducted in human subjects, none has found that acute stress affects salt intake. However, one study demonstrated that life stress (chronic stress) was associated with increased consumption of snack foods, which included, but not specifically, highly salty snacks. Studies investigating the influence of chronic stress on eating behaviours are required, including consumption of salty foods. From the available evidence, we can conclude that in free-living, Na-replete individuals, consuming Na in excess of physiological requirements, stress is unlikely to be a major contributor to salt intake.

In addition to soya-derived preparations, red clover-based dietary supplements have gained considerable interest as an alternative isoflavone (IF) source. While metabolism and bioavailability of the main IF from both sources have already been investigated, studies are still lacking on the biokinetic behaviour of IF, which are present in red clover in minor amounts. In the present pilot study, in which seven volunteers ingested a single dose of a commercial red clover dietary supplement, we focused on the absorption of three such IF, irilone (IRI), prunetin (PRUN) and pseudobaptigenin (PBAP). The compounds were measured as aglycones after enzymatic hydrolysis. A single intake of an amount of as low as 3·8 mg IRI (out of 38·8 mg IF in total) resulted in an IRI plasma concentration of 0·35 (sd 0·16) μm at 6.5 h post-ingestion. Compared to the plasma concentrations found for daidzein (0·39 μm) and genistein (0·06 μm), expected to be the main IF metabolites in plasma, the present findings indicate that IRI might possess a relatively high bioavailability. Furthermore, PRUN and PBAP were detected in human plasma for the first time.

Increasing attention has been paid to Spirulina for its potential clinical uses. The present study investigated the protection by dietary Spirulina platensis against d-galactosamine (d-GalN)- and acetaminophen (APAP)-induced hepatitis in ICR mice. Mice in each group (n 6) were fed with a standard diet (American Institute of Nutrition (AIN)-93G), a positive control diet containing 0·5 % butylated hydroxytoluene (BHT), or a diet containing 3, 6 or 9 % S. platensis for 1 week. On the last day the mice were treated with d-GalN (300 mg/kg body weight, intraperitoneally) or APAP (150 mg/kg body weight, intraperitoneally) and 24 h later the mice were killed. The doses of both 6 and 9 % S. platensis were found to significantly alleviate the increase of serum glutamate oxaloacetoacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities in d-GalN- or APAP-intoxicated mice. The observation was very similar to that of the positive control groups. Two more experiments were carried out to investigate the involvement of thiobarbituric acid-reactive substances (TBARS) and IL-18 in the suppression of 6 % S. platensis on d-GalN- and APAP-induced hepatitis. The significant increase of GOT and GPT activities was found to be accompanied with the elevation of hepatic TBARS level, IL-18 mRNA expression and serum IL-18 concentration, and was significantly alleviated by supplementation with 6 % S. platensis in diets. These results showed that dietary S. platensis could provide a significant protection against d-GalN- and APAP-induced liver injuries, and IL-18 and lipid peroxidation might be involved in the protective influence of S. platensis.

Prebiotic fibres have been proposed to promote weight loss and lower serum cholesterol; however, the mechanisms are not fully understood. The aim of the present research was to identify possible mechanisms through which prebiotic fibres improve serum lipids. Lean and obese JCR:La-cp rats aged 8 weeks consumed one of three diets supplemented with 0, 10 or 20 % prebiotic fibre for 10 weeks. Rats were anaesthetised and a fasting blood sample was taken for lipid analysis. Real-time PCR was used to determine gene expression for cholesterol and fatty acid regulatory genes in liver tissue. Liver and caecal digesta cholesterol and TAG content were quantified. Both doses of prebiotic fibre lowered serum cholesterol levels by 24 % in the obese hyperlipidaemic rats (P < 0·05). This change was associated with an increase in caecal digesta as well as an up-regulation of genes involved in cholesterol synthesis and bile production. Additionally, there was a 42 % reduction in TAG accumulation in the liver of the obese rats with 10 % prebiotic diet (P < 0·05); however, no change in liver fatty acid synthase (FAS). Prebiotic fibres appear to lower cholesterol levels through increased cholesterol excretion in the form of bile and inhibit the accumulation of TAG in the liver through a mechanism unrelated to FAS. These effects appear to be limited to the obese model and particularly the 10 % dose. The present work is significant as it provides insight into the mechanisms of action for prebiotic fibres on lipid metabolism and furthers the development of dietary treatments for hypercholesterolaemia.

Diets rich in fruits and vegetables are associated with lower risk of cancer which may be conferred in part by the antioxidant properties of these foods. However, antioxidant supplementation or increased consumption of antioxidant-rich foods has been reported to have inconsistent effects on DNA damage. The present work (the DART study) investigated the extent of inter-individual variation in DNA damage, the capacity for base excision repair (BER) and the responses of both variables to supplementation with an antioxidant supplement for 6 weeks. There was a wide inter-individual variation in endogenous lymphocyte DNA strand breaks (8-fold variation), in damage after a challenge with H2O2 (16-fold variation) and in DNA repair (41-fold variation) measured using the comet assay. When stratified into tertiles according to the pre-supplementation level of endogenous DNA damage, there was a statistically significant decrease in DNA damage after supplementation in the tertile with the highest pre-supplementation level of damage. There was no effect of supplementation on BER. Endogenous DNA damage level before supplementation was significantly different (P = 0·037) between the three genotypes for the Val16Ala single nucleotide polymorphism in manganese superoxide dismutase (rs4880) with individuals homozygous/wild type showing less damage than those carrying the alanine variant.

Leafy vegetables are important sources of provitamin A carotenoids. Information on their ability to provide vitamin A is often misleading because of the methodology used to assess bioefficacy. Mongolian gerbils were used to evaluate the bioefficacy of provitamin A carotenoids in tropical leafy vegetables (i.e. Solanum nigrum, Moringa oleifera, Vernonia calvoana and Hibiscus cannabinus) that are indigenous to Africa. Gerbils (n 67) were vitamin A-depleted for 5 weeks. After a baseline kill (n 7), the gerbils were weight-matched and assigned to six treatment groups (n 10; four vegetable groups; negative and positive controls). For 4 weeks, the treatments included 35 nmol vitamin A (theoretical concentrations based on 100 % bioefficacy) in the form of vegetables or retinyl acetate. In addition to their diets, the control and vegetable groups received daily doses of oil, while the vitamin A group received retinyl acetate in oil matched to prior day intake. Serum and livers were analysed for vitamin A using HPLC. Serum retinol concentrations did not differ among groups, but total liver vitamin A of the vitamin A and vegetable groups were higher than that of the negative control group (P < 0·0001). Liver β-carotene 15,15′-monooxygenase-1 expression levels were determined for two vegetable groups and were similar to the positive and negative controls. Conversion factors for the different leafy vegetables were between 1·9 and 2·3 μg β-carotene equivalents to 1 μg retinol. Small quantities of these vegetables maintained vitamin A status in gerbils through efficient bioconversion of β-carotene to retinol.

We have determined the absorption, conjugation and excretion of naringenin-7-O-rutinoside (narirutin) compared to the corresponding glucoside in an orange juice matrix in human subjects. Healthy volunteers (eight men and eight women), in a double blind, randomised, crossover study, consumed orange juice with (1) natural content of naringenin-7-O-rutinoside; (2) α-rhamnosidase-treated to yield naringenin-7-O-glucoside. Blood was sampled at twelve time points and three fractions of urine were collected over 24 h. The area under the plasma–time curve of naringenin from (2) α-rhamnosidase-treated orange juice was increased about 4-fold (P < 0·0001), peak plasma concentration (Cmax) was 5·4-fold higher (P < 0·0001) and Tmax was decreased from 311 to 92 min (P = 0·002) compared to untreated orange juice (1), indicating a change in absorption site from the colon to the small intestine. Furthermore, the amount in urine was increased from 7 to 47 % (P < 0·0001) of the dose after consumption of the α-rhamnosidase-treated orange juice (2). All urine samples contained both naringenin-7- and -4′-O-glucuronides. In addition, to examine the effect of dose and α-rhamnosidase treatment on hesperetin conjugate profiles, a further treatment where (3) orange juice fortified with three times the original content of hesperetin-7-O-rutinoside was used. Five hesperetin metabolites (3′-O-glucuronide; 7-O-glucuronide; 5,7-O-diglucuronide; 3′,7-O-diglucuronide; 3′-O-sulphate) were present after all treatments (1–3), with the same profile of the conjugates. The present data show that bioavailability of naringenin is increased by conversion from rutinoside to glucoside, but the profile of the conjugates of flavanones formed and excreted in urine is neither affected by the absorption site nor by a 3-fold change in dose.

The propensity of diets of different composition to promote obesity is a current topic in feline medicine. The effects of three meals with different protein:fat ratios on hormones (insulin, acylated ghrelin and amylin) involved in the control of food intake and glucose metabolism were compared. Five lean (two females and three males, 28·6 (sd 3·4) % body fat mass (BFM), mean body weight (BW) 4590 g) and five obese (two females and three males, 37·1 (sd 4·1) % BFM, mean BW 4670 g) adult cats were studied. Only BFM differed significantly between obese and lean cats. The cats were fed a high-protein (HP), a high-fat and a high-carbohydrate diet in a randomised cross-over design. Food intake did not differ between cats fed on the different diets, but obese cats consumed significantly more energy, expressed as per kg fat-free mass, than lean cats. After a 6-week adaptation period, a test meal was given and blood samples were collected before and 0, 30, 60 and 100 min after the meal. Baseline concentrations of glucose, amylin and acylated ghrelin were higher in obese cats than in lean cats, and obese cats showed the highest postprandial responses of glucose and amylin. The HP diet led to higher postprandial amylin concentrations than the other diets, indicating a possible effect of amino acids on β-cell secretion. Postprandial ghrelin concentrations were unaffected by diet composition. The relationship between insulin, amylin and ghrelin secretion and their relevant roles in food intake and glucose metabolism in cats require further study.

Lactobacilli isolated from various sources were identified on the basis of 16S–23S rRNA gene intergenic region amplification and subsequent sequencing of the smaller intergenic region. An in vitro analysis of probiotic properties including binding, ability to tolerate different concentrations of bile, survival in acidic buffer and antimicrobial activity of four different isolates and two standard strains (Lactobacillus plantarum American Type Culture Collection (ATCC) 8014 and L. rhamnosus GG (LGG)) was carried out. The ability of each isolate to stimulate Caco-2 cells, human peripheral blood mononuclear cells (PBMC) and THP-1 cells resulting in immunomodulation of these cells was analysed. Isolates L. rhamnosus CS25 and L. delbrueckii M and standard strain ATCC 8014 showed broad antimicrobial activity, and isolates CS25 (percentage of survival 6·9 % at pH 2·5, 5·1 % at pH 2·0) and L. plantarum CS23 (5·7 % at pH 2·5, 4·9 % at pH 2·0) have shown good tolerance to acidic pH. Isolate CS23 showed a good survival (14 %) after 2 h incubation in de Man, Rogosa and Sharpe (MRS) medium containing 3 % bile salts. Isolates CS23, CS25 and L. fermentum ASt1 could stimulate Caco-2 cells, human PBMC and THP-1 cells for a strong and varied immunomodulatory response in these cells. Though LGG showed poor antimicrobial activity as well as bile and acid tolerance, it was found to be the best binding strain tested. Child faecal isolate CS23 from the present study showed high binding ability (seventeen bacteria/Caco-2), high tolerance to acidic pH and bile salts and significant immunomodulation; therefore it is a good potential probiotic candidate.

Elevated plasma total homocysteine (tHcy) is a risk factor for vascular disease but lowering tHcy with B-vitamins, including folate, has generally not reduced vascular events in secondary prevention trials. Elevated plasma S-adenosylhomocysteine (AdoHcy) concentration may be a more sensitive indicator of vascular disease than plasma tHcy. However, unlike tHcy, plasma AdoHcy did not correlate with folate concentration in one study indicating that folate supplementation may not lower AdoHcy. Our aim was to determine whether providing B-vitamin supplements to healthy older people with elevated tHcy (>13 μmol/l) affects plasma AdoHcy and S-adenosylmethionine (AdoMet) concentrations. Healthy older participants (n 276; ≥ 65 years) were randomised to receive a daily supplement containing folate (1 mg), vitamin B12 (500 μg) and vitamin B6 (10 mg), or placebo, for 2 years. Of these participants, we selected the first fifty participants in each treatment group and measured plasma AdoHcy and AdoMet. Plasma tHcy was 4·4 (95 % CI 3·2, 5·6; P < 0·001) μmol/l lower at 2 years in the vitamins group compared with the placebo group. At 2 years, there were no significant differences in plasma AdoMet (+4 % (95 % CI − 2, 11); P = 0·19), AdoHcy ( − 1 % (95 % CI − 10, 8); P = 0·61) or the AdoMet:AdoHcy ratio (0·22 (95 % CI − 0·04, 0·49); P = 0·10) between the two groups. In conclusion, B-vitamin supplementation of older people lowered plasma tHcy but had no effect on plasma AdoMet or AdoHcy concentration. If elevated plasma AdoHcy is detrimental, this may explain why B-vitamins have generally failed to reduce vascular events in clinical trials.

The provision of parenteral nutrition (PN) to ‘stressed’ patients often results in hyperglycaemia, which may be detrimental. In animal models limited amounts of enteral nutrition (EN) improve intestinal integrity and stimulate intestinal incretin production, which may lead to improved glucose control. We set out to assess if combining EN with PN results in improved glucose homeostasis rather than PN given alone. We conducted a randomised trial in a university teaching hospital of patients undergoing a ‘curative’ oesophagectomy for adenocarcinoma. Differences between the two intervention groups were assessed for continuous glucose measurement, insulin sensitivity using insulin tolerance tests (ITT) and homeostasis model analysis (HOMA), the incretin glucose-dependent insulinotropic polypeptide (GIP) and intestinal permeability. The combination of PN with EN resulted in lower interstitial glucose concentrations (P = 0·002), reduced insulin resistance, improved insulin sensitivity (HOMA-insulin resistance (IR) P = 0·045; HOMA β P = 0·037; ITT P = 0·006), improved intestinal permeability (P < 0·001) and increased GIP (P = 0·01) when compared with PN alone. The combination of EN with PN, when compared with PN alone, results in reduced glucose concentrations, reduced insulin resistance, increased incretins and improvements in intestinal permeability.

To compare the glycaemic index (GI) of newly developed ‘atta mix’ roti with whole wheat flour roti. Eighteen healthy non-diabetic subjects consumed 50 g available carbohydrate portions of a reference food (glucose) and two test foods (whole wheat flour roti and atta mix roti) in random order after an overnight fast. The reference food was tested on three separate occasions, while the test foods were each tested once. Capillary blood samples were measured from finger-prick samples in fasted subjects ( − 5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min from the start of each food. No significant difference was observed between roti prepared from whole wheat flour and atta mix in terms of appearance, texture, flavour, taste or acceptability. For each test food, the incremental area under the curve and GI values were determined. The GI of atta mix roti (27·3 (sem 2·2)) was considerably lower than the whole wheat flour roti (45·1 (sem 3·5), P < 0·001). Development of foods with lower dietary glycaemic load such as the atta mix roti could help in the prevention and control of diabetes in South Asian populations, which habitually consume very high glycaemic load diets.

Maternal supplementation with long-chain PUFA, to improve infant neurological development, might cause additional increase of oxidative stress. Pregnant women aged 18–41 years were randomised into one of four supplementation groups. From week 22 on, they received supplements containing either modified fish oil (n 69), 5-methyl-tetrahydro-folate (n 65), both (n 64), or placebo (n 72). Plasma Trolox-equivalent antioxidative capacity (TEAC), concentrations of α-tocopherol, retinol, β-carotene, free thiol groups, uric acid and thiobarbituric acid-reactive substances (TBARS) were determined at weeks 20 and 30 and at delivery. The studied antioxidants showed no significant differences between the four supplementation groups. At week 30 plasma TBARS levels were found to be significantly higher in the fish oil group (0·80 (sem 0·04) μmol/l) than in the folate (0·67 (sem 0·03) μmol/l; P = 0·024) and control (0·69 (sem 0·04) μmol/l; P = 0·01) groups. Concentrations of retinol and free thiol groups decreased during pregnancy, whereas uric acid increased and β-carotene as well as TEAC showed only minor changes. Fish oil supplementation during the second half of pregnancy appears not to decrease antioxidant status. The increased TBARS levels at week 30 may indicate a period of increased oxidative stress in plasma at this time.

The aim of the present work was to assess the prevalence of the Mediterranean dietary pattern (MDP) in Balearic Islands adolescents, and socio-demographic and lifestyle factors that might determine adherence to the MDP. A cross-sectional nutritional survey was carried out in the Balearic Islands between 2007 and 2008. A random sample (n 1231) of the adolescent population (12–17 years old) was interviewed. Dietary questionnaires and a general questionnaire incorporating questions related to socio-economic status, parental education level and lifestyle factors were used. Dietary habits were assessed by means of two 24 h recalls and a quantitative FFQ. Adherence to the MDP was defined according to a score constructed considering the consumption of nine MDP characteristic components: high MUFA:SFA ratio, moderate ethanol consumption, high legumes, cereals and roots, fruits, vegetables and fish consumption, and low consumption of meat and milk. Then, socio-demographic, lifestyle and health status variables that could determine a higher or ower adherence were assessed. The mean adherence was 57·9 (sd 8·9) % and the median adherence was 57·3 %. Half of the Balearic Islands adolescents (50·5 %) showed an adherence to the MDP comprised between 52·7 and 62·8 %. By multivariate analyses, a high maternal level of education, increased physical activity, reduced alcohol intake and abstinence from smoking were independent associations of better adherence to the MDP. The promotion of not only the MDP but also the Mediterranean lifestyle, including greater physical activity, should be reinforced among the Balearic younger generations.

Maternal nutritional status before and during pregnancy is important for the growth and development of the fetus. The effects of pre-pregnancy nutrition (estimated by maternal size) are well documented. There is little information in today's Western society on the effect of maternal nutrition during pregnancy on the fetus. The aim of the study was to describe dietary patterns of a cohort of mothers during pregnancy (using principal components analysis with a varimax rotation) and assess the effect of these dietary patterns on the risk of delivering a small-for-gestational-age (SGA) baby. The study was a case–control study investigating factors related to SGA. The population was 1714 subjects in Auckland, New Zealand, born between October 1995 and November 1997, about half of whom were born SGA ( ≤ 10th percentile for sex and gestation). Maternal dietary information was collected using FFQ after delivery for the first and last months of pregnancy. Three dietary patterns (traditional, junk and fusion) were defined. Factors associated with these dietary patterns when examined in multivariable analyses included marital status, maternal weight, maternal age and ethnicity. In multivariable analysis, mothers who had higher ‘traditional’ diet scores in early pregnancy were less likely to deliver a SGA infant (OR = 0·86; 95 % CI 0·75, 0·99). Maternal diet, particularly in early pregnancy, is important for the development of the fetus. Socio-demographic factors tend to be significantly related to dietary patterns, suggesting that extra resources may be necessary for disadvantaged mothers to ensure good nutrition in pregnancy.

The aim of the present study was to verify whether extra-virgin olive oil, a dietary component naturally containing phenolic antioxidants, has the potential to protect the brain from the deleterious effects of ageing. To accomplish this goal, we used male rats fed a high-energy diet containing either maize oil, or extra-virgin olive oil with high or low phenol content (720 or 10 mg total phenols/kg oil, corresponding to a daily dose of 4 or 0·05 mg total phenols/kg body weight, respectively) from age 12 months to senescence. The measured endpoints were biochemical parameters related to oxidative stress and functional tests to evaluate motor, cognitive and emotional behaviour. Olive oil phenols did not exert major protective actions on motor and cognitive function, as we observed only a tendency to improved motor coordination on the rotarod in the old animals treated with the oil rich in phenols (40 % average increase in the time to first fall; P = 0·18). However, an interesting finding of the present study was a reduced step-through latency in the light–dark box test, found in the older animals upon treatment with the oil rich in antioxidant phenols, possibly indicating an anxiety-lowering effect. This effect was associated with decreased glutathione reductase activity and expression in the brain, a phenomenon previously associated with decreased anxiety in rodents. These results indicate a previously undetected effect of a diet containing an olive oil rich in phenols. Further studies are warranted to verify whether specific food antioxidants might also have an effect on emotional behaviour.

The UK Food Standards Agency convened a workshop on 13 May 2009 to discuss recently completed research on diet and immune function. The objective of the workshop was to review this research and to establish priorities for future research. Several of the trials presented at the workshop showed some effect of nutritional interventions (e.g. vitamin D, Zn, Se) on immune parameters. One trial found that increased fruit and vegetable intake may improve the antibody response to pneumococcal vaccination in older people. The workshop highlighted the need to further clarify the potential public health relevance of observed nutrition-related changes in immune function, e.g. susceptibility to infections and infectious morbidity.

This report summarises a workshop convened by the UK Food Standards Agency (FSA) on 14 October 2008 to discuss current FSA-funded research on carbohydrates and cardiovascular health. The objective of this workshop was to discuss the results of recent research and to identify any areas which could inform future FSA research calls. This workshop highlighted that the FSA is currently funding some of the largest, well-powered intervention trials investigating the type of fat and carbohydrate, whole grains and fruit and vegetables, on various CVD risk factors. Results of these trials will make a substantive contribution to the evidence on diet and cardiovascular risk.